Wyeast contradiction

[anbowden]

Hi guys, I'm very new to homebrewing and just recently brewed my third extract kit with liquid yeast. Upon researching whether I needed a starter I found two things that seem to contradict each other:
1. Wyeast Activator information from the website:
http://www.wyeastlab.com/hb_productdetail.cfm?ProductID=16
"The Activator™ package contains a minimum of 100 billion cells in a yeast slurry.. The Activator™ is designed to directly inoculate 5 gallons of standard strength ale wort (1.034-1.060 SG) with professional pitching rates"

2. Greg Doss from Wyeast, "Know your pitch rates":

Using a pitch rate calculator from mrmalty.com, it says I'd need to make a little over 2 liter starter("Simple Starter") for a 1.060 SG beer.

So, I've seen on this forum where people refer to Wyeast's website for information(e.g. "What if my smack pack doesn't swell"), but never this piece of information. So, what gives?

Thanks,
Andy

 

[LoneWolfPR]

I've never had a problem pitching a single pack into a beer up to 1.060.

 

[kaconga]

The optimal pitching rate is different than an acceptable pitching rate. A starter is pretty much always required to reach optimal rates with liquid yeast. Your beer can and will ferment at lower pitch rates but it might have more fruity esters or be more likely to get stuck.

 

[Yooper]

The optimal pitching rate is different than an acceptable pitching rate. A starter is pretty much always required to reach optimal rates with liquid yeast. Your beer can and will ferment at lower pitch rates but it might have more fruity esters or be more likely to get stuck.

Right. "Acceptable" isn't optimum, but it will work. It will make beer. Will it make good beer? Probably, maybe even great. But will underpitching make the best beer? No.

Using proper pitch rates, at the proper temperature (NOT 75 degrees and then lowering it) and keeping optimum fermentation temperature steady for the fermentation will guarantee the best results possible.

 

[mathin]

What is the science around under pitching causing problems? Just curious, not saying it isn't true.

 

[Tantalus]

@mathin: Yeast emit certain flavor compounds, esters and phenols among them, much more during reproduction and growth phases than during the phase when your colony is pretty much established. This also has to do with exposure to oxygen and the resulting aerobic respiration that takes place. Sometimes this can be desirable (i.e. usually in controlled amounts) but too many of these flavor compounds may overwhelm the other flavors in your beer.

@Yooper: Will keeping my starters at room temperature before cold crashing them affect viability?

 

[Yooper]

What is the science around under pitching causing problems? Just curious, not saying it isn't true.

I'm no scientist! I have to defer to the experts on the science behind it. I really like the easy articles about yeast on mrmalty.com: http://www.mrmalty.com/starter_faq.php

@Yooper: Will keeping my starters at room temperature before cold crashing them affect viability?

No. Even lager starters are commonly fermented at room temperature. You don't want to cold crash for an inordinate amount of time (otherwise you'd have to make a starter for your starter ) for for a day or two or so, it works fine. For my larger starters, I always decant before pitching so sticking them in the fridge works great. I leave them in there overnight (longer for lager yeast), and then decant the spent wort and pitch the yeast into my brew.

 

[Boerderij_Kabouter]

Under pitching isn't in itself a problem. Indeed, many times an under pitch is the desireable pitching rate. Very basically, when you under pitch (inoculate with a relative small number of yeast cells), the yeast will reproduce more and each yeast cell will be counted on to do more work. This results in the production of relatively more yeast byproducts (esters, acyldahyde, sulfur, whathaveyou). In most cases, for new brewers, under pitching is a bad idea because you are likely not doing it on purpose and are not controlling the other fermentation practices as tightly as could be. Then, an under pitch often leads to excessive "off-flavored" compounds remaining in the finished beer.

That is why the common practice is to make a starter culture.

 

[Yooper]

Under pitching isn't in itself a problem. Indeed, many times an under pitch is the desireable pitching rate. Very basically, when you under pitch (inoculate with a relative small number of yeast cells), the yeast will reproduce more and each yeast cell will be counted on to do more work. This results in the production of relatively more yeast byproducts (esters, acyldahyde, sulfur, whathaveyou). In most cases, for new brewers, under pitching is a bad idea because you are likely not doing it on purpose and are not controlling the other fermentation practices as tightly as could be. Then, an under pitch often leads to excessive "off-flavored" compounds remaining in the finished beer.

That is why the common practice is to make a starter culture.

That's an excellent point. I didn't think about that, but it's true that sometimes the esters/phenols are a desirable thing.

One other thing that I think is important to note- as a "compensation" to underpitching, the two major liquid yeast manufacturer's say something on the package like "pitch in 75 degree wort and hold until signs of fermentation appear, and then lower to the appropriate temperature". That's good advice if your goal is to grow more yeast- but it's not the way to make the best tasting beer. It's simply trying to compensate for an inadequate amount of yeast in the first place. In my experience, it usually makes better beer to pitch the proper amount of yeast at the proper temperature (or even a tad bit below the optimum fermentation temperature and let it rise).

 

[mathin]

Thanks for all the good information! When I understand the "why" of something I'm more likely to take it seriously.

 

[jfr1111]

We must not forget that we, as forum goers and home brew fanatics, are a relatively small percentage of a small group: when wyeast says on the package to pitch in 1.060 worth without making a starter, they are adressing the vast majority of homebrewers: the guys and gals who are after beer and maybe have just finished graduating from the mr. beer kit. They are hedging their bets: as a beginner, I had no idea how to make a starter culture, let alone a good one. And even if I had, I would probably have messed it up. I suspect that the "sprinkle" instructions on the Safale packets of dry yeast stems from the same reasoning. They know that hydrating is better since it will usualy yield better viability, but they know that their target group might botch it and infect the beer. So they say to sprinkle.

Smacking a pack and pouring it in wort is easy. It'll make beer. Just as pitching a whole beer on a cake from a previous brew. It's not optimal, but you don't need to be after optimal. Optimal would be keeping the pure culture on slants in a dedicated freezer and doing cell counts before pitching, because even yeast calculators only give you approximations, but that's not practical for most of us.

 

[GilaMinumBeer]

Under pitching isn't in itself a problem. Indeed, many times an under pitch is the desireable pitching rate.

This. Pitch rate is simply another metric of control to a desired end. the key is to have a reasonable grasp of what a given rate is per strain to begin to understand what can be achieved.